Open end harrow and framework therefor



April 14, 1964 E. J. BIRKENBACH ET'AL 3,128,834

OPEN END HARROW AND FRAMEWORK THEREFOR Filed March 22, 1961 United States Patent 3,128,834 OPEN END HARROW AND FRAMEWORK THEREFOR Eugen J. Birkenbach, Park Ridge, and Daniel M. ONeill, Naperville, IlL, assignors to International Harvester Company, Chicago, Ill., a corporation of New Jersey Filed Mar. 22, 1961, Ser. No. 97,566 1 Claim. (Cl. 172-635) This invention relates to agricultural implements and more particularly to a type used for penetrating and scarifying the earth.

Peg-tooth harrows are generally very well known. Their construction has in general been pretty much standardized in the past and required, particularly in the types which are settable to different working positions, pivotal connections to the draft members which are offset from the tooth bars. In view of the forces involved, it required that the pivotal connections be made extremely strong to withstand the loads and at the same time in view of the connections used, the flexibility of the harrow has been impaired.

A general object of the invention is to provide a novel spike or peg-tooth harrow wherein the frame members are integrated into a design utilizing the tooth bars as part of the frame structure in addition to their carrying the teeth.

A still further object of the invention is to provide a novel open end peg-tooth harrow wherein the tooth bar is supported for pivotal movement through the longitudinal draft elements whereby the entire transverse strength of the tooth bars are utilized in resisting loads.

A further object of the invention is to provide a novel pivotal mounting and connection for the tooth bar with the draft element, the connection serving not only as a positioning means lengthwise of the longitudinal element, but also as a bearing for pivotal movements of the tooth bar.

These and other objects and advantages inherent in and encompassed by the invention will become more readily apparent from the specification and the drawings, where- FIG. 1 is a perspective view of the novel harrow;

FIG. 2 is a sectional view taken substantially on the line 2-2 of FIG. *1;

FIG. 3 is a further sectional View taken substantially on the line 3--3 of FIG. 1; and

FIG. 4 is a plan view of one of the 'bearing parts.

Describing the invention in detail and having particular reference to the drawings, there is shown an open end harrow 2 comprising a plurality of transverse tooth bars 3, 3 which are disposed in parallel fore-and-aft spaced relationship transverse to the direction of movement of the harrow. The tooth bars in the present instance are each formed of a pair of opposed angle irons 4 and 5, which collectively develop a box section, and which receive therebetween and are welded to a plurality of dependent teeth 6, 6. Each bar, substantially centrally thereof, is connected by means of a U-shaped clamp 7 to the lower end of an upwardly directed arm 8 which adjacent to its lower end is pivoted as by means of a pin 10 to the lower link or bar element 11 of the set bar assembly, generally designated 12. The bar 11 extends longitudinally fore and aft of the harrow and overlays the bars 3, 3 and extends substantially parallel with the upper link 13 which is connected by means of pins 14 at longitudinally spaced points to the upper ends of the respective arms 8. The rearwardmost arm 8 is provided with a set lever 15 by means of which the entire linkage is controlled in a foreand-aft direction rotating the respective tooth bars in order to control the attitude of the teeth. The arm 8 which is "Ice second from the front of the harrow, the front being designated 16, is provided with an extension 17 which has its upper end pivotally connected as at 18 to a shock absorbing unit 19 which includes an adjusting bar 26 with a plurality of notches 21 complementally receiving a pin 22 which is mounted on the upper end of an arm 23 which is connected to the lower link 11 of the operating linkage adjacent to the rear end thereof. It will be appreciated that by the positioning of the bar 20, with respect to the pin 22, a desired adjustment of the tooth bars is obtained, as is well known to those skilled in the art.

It will be noted from a consideration of FIG. '1 that the harrow is provided with a pair of longitudinal draft and spacer beam structures 25, 25 which are disposed substantially medially between the center of the bar and the adjacent end 26 of the bar. Each structure 25 comprises upper and lower straps 27 and 28 which are disposed respectively above and below the bars 3 and at the forward ends merge into a loop 29 which serves as a means of attachment to an associated hitching means, such as a cable or the like.

The members 27 and 28 are interconnected to each bar 3 by a novel bearing structure generally indicated 30. Each bearing structure comprises complementary identical upper and lower halves 31, 31, each of which includes laterally offset longitudinally spaced generally parallel flat mounting segments 32 and 33 interconnected by an arcuate segment 34. The upper segment 32 has intermediate its lateral edges a lug 35 punched out therefrom and the lug 35 is depressed inwardly of the portion 32 and formed as a continuation of the arcuate contour of the arcuate bearing section 30 so that the section 34 and the lug 35 substantially provide a semi-circular bearing portion. The free end 36 of each lug 35 enters a slot 37 in the base end of portion 34 of the other bearing half 31. It will be observed that in the assembled position of the bearing elements 31, 31 that they are assembled to closely embrace the beam 3 and provide a substantially circular bearing therefor.

Thus it will be seen that the bearing structure not only serves as a structural means between the upper and lower strap portions 27 and 28, but also provides a bearing for the associated beam.

Another feature of the invention resides in the provision of a plurality of alignment or separator beams 40, 49 which extend generally parallel to the beams-3, 3 beneath the lower set bar element 11 and at opposite ends is connected as by rivets at 41, 41 to the top straps 27, 27 of the spaced draft elements 25, 25. The center portion of the bar 40 is connected to a 'U-shaped securing element 42 which has a slidable association with the lower bar 11 and so that upon the bars encountering shocks the shock absorbing mechanism is allowed to operate by permitting longitudinal reciprocation of the bar 11. It will be seen, as well illustrated in FIGURE 3, that the securing element 42 is of inverted U-shape and has a bight portion 44 overlapping the bar 11 and has a pair of laterally spaced vertical leg portions 45 and 46 snugly embracing the beam 11 therebetween and that the lower ends of the legs 45 and 46 are provided with outturned securing lugs 47 and 48 which are secured to the spreader bar 40 by means of rivets or the like at 49 and 50. The U-connection permits the draft elements to be drawn up to engage the bearings with the tooth bars.

Thus it will be seen that a novel simple harrow is provided which has a skeleton framework of novel construction wherein the various members of the framework serve in optimum capacity not only as structural members but also in loading the beams to maximum advantage.

What is claimed is:

In an open end harrow, a unitary framework comprising a pair of laterally spaced longitudinal draft ele- 3 ments each having a plurality of transverse openings, at least two spreader elements extending transversely of said draft elements and interconnecting the same, a pair of laterally spaced guiding means connected to each of said spreader elements intermediate said draft elements and defining cooperative guiding slots; a plurality of tooth bars extending transversely of said draft elements laterally beyond the same through said openings therein providing a pivotal mounting for said tooth bars to said draft elements, an operating linkage associated with the 10 bars for setting them in a plurality of Working positions and including a longitudinal member connected to and movable with the tooth bars and having slidable guided engagement within said guiding slots, and shock absorbresisting movement thereof in response to actuation thereby by the tooth bars pivoting away from an obstruction.

References Cited in the file of this patent UNITED STATES PATENTS 597,201 Lean et a] Jan. 11, 1898 638,393 Duvall Dec. 5, 1899 910,541 Horner Jan. 26, 1909 2,580,119 Meyers Dec. 25, 1951 2,629,217 Kuehn et a1. Feb. 24, 1953 2,872,253 Foote et al. Feb. 3, 1959 2,979,139 Birkenbach et al. Apr. 11, 1961 

